1. Field of the Invention
This invention relates to a quick connect system for excavator buckets and other tools which allow an excavator bucket to be connected quickly to the arm of a hydraulic excavator or front end loader or the like. In use, excavator buckets often need to be replaced several times during a shift at significant time and with substantial difficulty. The subject invention, has a plurality of mounting assemblies which allow the pins which are attached to the arm of a hydraulic excavator to be easily placed into position into the mounting assemblies fixed to an excavator bucket. A cover plate which can be hinged or pivotally mounted on each mounting assembly, is bolted into place to fix the pin securely to the excavator bucket. A preferred embodiment utilizes a locking head on one end of each pin and a retaining clamp on the other end of each pin to secure the pins to the excavator bucket.
2. Description of Related Art
Conventional buckets typically have a pair of plates having apertures or openings through which a pair of large pins are driven to connect the bucket to a hydraulic arm. Each pin goes through a bushing in the hydraulic arm as well as the openings in the plates attached to the bucket. The problem with attaching conventional excavator buckets to the arm of an excavator is that the pins must be driven through the opening in one mounting plate through the bushing in the arm of the excavator and then through the opening in the other mounting plate to attach the bucket. Any misalignment causes great difficulty in attaching the bucket to the arm. Further, it is difficult to align the holes in the plates of the heavy excavator buckets with the bushing and the pin so that the pin can be driven through without galling or scoring the openings. To enable insertion and removal of the pins, there has to be significant tolerances in the holes in the plates. These tolerances cause wear over time. The subject invention clamps the pin securely so that it does not move within the mounting assembly and little or no wear occurs between the pin and the opening. Considerable effort must also be used to drive the pins out of the openings. In use, buckets may need to be replaced several times per day and it usually takes 25 to 30 minutes to change a conventional bucket. With the quick connect system of this invention, time is minimized and the changing of buckets is greatly facilitated.
Dejana U.S. Pat. No. 4,769,933 discloses a snow plow assembly for a payloader that has a pair of quick connect pin units for connecting a snowplow blade in front of an excavator bucket.
Arnold U.S. Pat. No. 5,332,353 discloses a quick coupler for excavation equipment. This patent discloses a latch mechanism which allows an excavator bucket to be coupled to heavy construction equipment.
Lenertz et al. U.S. Pat. No. 4,436,477 discloses a quick attachment carrier assembly with latch hooks for engaging a bucket or the like to the arm of a front end loader.
Kaczmarczyk et al. U.S. Pat. No. 4,986,722 discloses a mounting structure for a loader attachment that includes a spring loaded latching pin for securing the pin of a hydraulic arm to the bucket.
Tibbatts et al. U.S. Pat. No. 5,141,385 discloses an implement attachment coupler in which each pin is held in the end of its respective loader arm by a spring loaded latch.
McCain U.S. Pat. No. 4,397,604 also discloses a releasable mechanism for attaching a bucket to a backhoe which includes latching means.
None of the foregoing have suggested a simple and inexpensive solution to the easy connection of excavator buckets to arms of hydraulic excavator equipment. Each of these typically add mechanisms or structure to the end of the hydraulic arm which adds weight and increases the pin-to-tip radius, which in turn increases the breakout force required to move the bucket through the material to be excavated. The subject invention does not adversely effect the breakout force and also does not add weight to either the bucket or the arm as the foregoing prior art systems have done. Furthermore, the subject invention requires no latching mechanisms.
Excavators are rated in lifting capacity and breakout force. Adding weight by adding any of the latching mechanisms of the prior art devices, decreases the lifting capacity of the machine. The breakout force is the force required to move the bucket through the material to be excavated. The longer the pin-to-tip radius, the more breakout force is required. By maintaining the pin-to-tip radius specified by the manufacturer and by avoiding any weight increase, the performance of the excavator is optimized.